Subaru Legacy 2004 Service Manual page 1234

COOLING
Step
23 CHECK HARNESS BETWEEN MAIN FAN
RELAY 1 AND ECM.
1) Disconnect the connector from ECM.
2) Measure the resistance between main fan
relay 1 terminal and ECM connector.
Connector & terminal
(B135) No. 24 — (B143) No. 7:
24 CHECK HARNESS BETWEEN MAIN FAN
RELAY 2 AND ECM.
Measure the resistance between main fan
relay 2 terminal and ECM connector.
Connector & terminal
(B135) No. 24 — (F27) No. 3:
25 CHECK FUSE.
1) Turn the ignition switch to OFF.
2) Remove the fuse No. 2 and No. 26.
3) Check the condition of fuse.
26 CHECK POOR CONTACT.
Check poor contact in ECM connector.
27 CHECK OPERATION OF RADIATOR FAN.
Check the sub fan rotates when both fans do
not rotate at high speed under the step 2.
28 CHECK GROUND CIRCUIT OF MAIN FAN
RELAY 2.
1) Remove the main fan relay 2 from A/C relay
holder.
2) Measure the resistance between main fan
relay 2 terminal and chassis ground.
Connector & terminal
(F27) No. 4 — Chassis ground:
29 CHECK POWER SUPPLY TO MAIN FAN RE-
LAY 2.
1) Turn the ignition switch to ON.
2) Measure the voltage between main fan
relay 2 terminal and chassis ground.
Connector & terminal
(F27) No. 1 (+) — Chassis ground (
30 CHECK MAIN FAN RELAY 2.
1) Turn the ignition switch to OFF.
2) Remove the main fan relay 2.
3) Measure the resistance of main fan relay 2.
Terminals
(F27) No. 4 — (F27) No. 5:
31 CHECK MAIN FAN RELAY 2.
1) Connect the battery to terminals No. 1 and
No. 3 of main fan relay 2.
2) Measure the resistance of main fan relay 2.
Terminals
(F27) No. 4 — (F27) No. 5:
Radiator Fan System
Check
Is the resistance less than 1
(?
Is the resistance less than 1
(?
Is the fuse blown out?
Is there a poor contact in ECM
connector?
Does the sub fan rotate?
Is the resistance less than 1
(?
Is the voltage more than 10 V? Go to step 30.
$
):
Is the resistance more than 1
M(?
Is the resistance less than 1
(?
CO(H4DOTC)-12
Yes
Go to step 24. Repair the open
circuit of harness
between main fan
relay 1 terminal
and ECM.
Go to step 25. Repair the open
circuit of harness
between main fan
relay 2 terminal
and ECM.
Replace the fuse. Go to step 26.
Repair the poor Repair the power
contact in ECM supply circuit for
connector. main fuse box.
Go to step 20. Go to step 28.
Go to step 29. Repair the open
circuit in harness
between main fan
relay 2 and chas-
sis ground.
Repair the power
supply line.
Go to step 31. Replace the main
fan relay 2.
Go to step 23. Replace the main
fan relay 2.
No